package com.hmdp.utils;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
public class RedisIdWorker {

  private static final long  BEGIN_TIMESTAMP = 1640995200L;
    /**
     * 序列号的位数
     */
    private static final int COUNT_BITS=32;

    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    public long nextId(String keyPrefix){
        //1.生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timestamp = nowSecond-BEGIN_TIMESTAMP;

        //2.生成序列号
        //2.1获取当前日期，精确到天
        String data = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        //2.2自增长
        long count = stringRedisTemplate.opsForValue().increment("icr" + keyPrefix + ":" + data);

        //3.返回并拼接
        return timestamp << COUNT_BITS | count;
    }


    /*public static void main(String[] args) {
        LocalDateTime time = LocalDateTime.of(2022, 1, 1, 0, 0, 0);
        long second = time.toEpochSecond(ZoneOffset.UTC);
        System.out.println("second="+second);
    }*/
}
